SO? incase you haven't realized there's a thing called the internet where you can look stuff up. the horses are small and disproportionate, it's fine these things happen when drawing, just don't try to give an excuse to the mistakes made (for instance the end credits to Isekai Maou to Shoukan Shoujo no Dorei Majutsu the elf girl looks like she has a few extra vertebrae in her spine) it valid criticism of the work. the story is set in a European style setting the characters are described and have a more mature look at younger ages like Europeans the builds are stylized the same way you think these people that tower over the mc saw these tiny horses and thought "yep, perfect to ride into battle with!" or the artist can't draw them well?
everything is European like except the breading of bigger warhorses? right sure.